在gral plot中设置放大会导致空图

Question

我有以下代码用于为我的数据生成图表：

import // ...    
import javax.swing.JFrame;
import de.erichseifert.gral.data.DataTable;
import de.erichseifert.gral.io.plots.DrawableWriterFactory;
import de.erichseifert.gral.plots.XYPlot;
import de.erichseifert.gral.plots.lines.DefaultLineRenderer2D;
import de.erichseifert.gral.plots.lines.LineRenderer;
import de.erichseifert.gral.ui.InteractivePanel;

public class Plot extends JFrame {
    private static final long serialVersionUID = 8083971727860355817L;

    private int width   = 1366;
    private int height  = 768;

    public Plot(String filename) {
        super(filename);
        setDefaultCloseOperation(EXIT_ON_CLOSE);
        setSize(width - 10, height -40 );
    }

    @SuppressWarnings("unchecked")
    public void showGraph(List<Integer> x, List<Double> y, boolean saveFile){

        DataTable data = new DataTable(Integer.class, Double.class);
        for (int i = 0; i < x.size(); i++) {
            data.add(x.get(i), y.get(i));
        }

        XYPlot plot = new XYPlot(data);

        // Draw a tick mark and a grid line every 10 units along x axis
        int x_scale = 1;
        if (x.size() > 20){
            Collections.sort(x);
            x_scale = x.get(y.size()-1) / 10;
        }
        plot.getAxisRenderer(XYPlot.AXIS_X).setTickSpacing(x_scale);
        // Draw a tick mark and a grid line every 20 units along y axis
        plot.getAxisRenderer(XYPlot.AXIS_Y).setTickSpacing(0.05);

        LineRenderer lines = new DefaultLineRenderer2D();
        plot.setLineRenderer(data, lines);

        Color color = new Color(0.0f, 0.3f, 1.0f);
        plot.getPointRenderer(data).setColor(color);
        plot.getLineRenderer(data).setColor(color);

        getContentPane().add(new InteractivePanel(plot));
        // Zooming results in empty plot :( 
            //plot.getNavigator().setZoom(2f);
    }
// ...
}

如果我取消注释设置缩放的最后一行

plot.getNavigator().setZoom(2f);

我会得到一个空的情节。有任何建议如何使它工作？